OpenAPI Linter Online — Style Rules for Specs
Lint OpenAPI 3.x style rules (Spectral-style subset) — path operations only, 100% in-browser.
Developer notes
• Custom Spectral-style subset — not full Spectral OAS. • Operations under paths only (not webhooks/callbacks in v1). • Rules: not-openapi, operation-operationId, operation-tags, info-contact, info-description, paths-kebab-case, operation-success-response, operation-description. • Live debounced lint; Monaco JSON/YAML input. • Status: passed / passed with warnings / failed. • Max input 512 KiB. • Results panel shows rule counts, issue paths, and spec stats.
Use cases
• Enforce operationId, tags, and 2xx responses on path operations. • Spot missing info.contact / description before publishing. • Prefer kebab-case path segments (or vN).
Examples
Warnings for missing operationId
Before
After
default-only responses fail
Before
After
Lint OpenAPI FAQ
Common questions
Is this full Spectral?
No. v1 ships a fixed Spectral-style subset listed in the developer notes — not a custom ruleset runner.
Which operations are linted?
Only path operations (get/put/post/delete/options/head/patch/trace). webhooks and callbacks are out of scope in v1.
What do passed / passed with warnings / failed mean?
failed = any error-level issue; passed with warnings = warnings only; passed = no issues. We never show a plain green “valid” when warnings exist.
Does lint run schema validate?
No. Lint requires openapi 3.x + info, then style rules. Use Validate OpenAPI for full schema conformance.
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